1,721,015 research outputs found
Auxin application and cutting length affect rooting in Cuphea hyssopifolia stem cuttings
No full textThe effect of cutting length and indole-3-buyric acid (IBA) application on adventitious root formation stem cuttings was studied in Cuphea hyssopifolia. Softwood terminal cuttings of a clone grown in Sicily were trimmed to three lengths (2, 4 or 6 cm) and inserted to a 1-cm depth in bottom heated plastic trays containing a humidified peat-vermiculite mixture 1:2 (v/v). To verify the cutting response to different auxin concentrations, cuttings were dipped to a 1.0 cm depth in a 500ppm or 1000 ppm IBA solutions for 10 seconds.
Cutting percent survival was 100%. Regardless of cutting length, the highest rooting percentage was obtained with IBA at 1000 ppm (avg. 86.7%), whereas rooting significantly declined to 73% and 81%, in absence of IBA and at 500 ppm IBA, respectively. Percentage rooting averaged over IBA treatment accounted for 93.3% and 90% in 6 and 4 cm long cutting treatments,
espectively. The lowest percentage of rooting was recorded with the 2 cm cutting treatments (59%). Cutting length and IBA application significantly interacted as percentage rooting ranged from 43% in 2 cm long cuttings rooted in absence of IBA to 100% in 4 cm long cuttings with 1000 ppm IBA. The highest number of roots was observed from cuttings exposed to IBA at 500 and 1000 ppm (19.7 and 19.6 roots per cutting, respectively). Root number significantly declined in absence of IBA (16.8 roots per cutting). Our results demonstrated that the use of 4 or 6 cm long cuttings and the application of 1000 ppm IBA for 10 seconds could induce optimal adventitious root formation in C. hyssopifolia. The application of the technique described would enhance propagation of this valuable ornamental species
Comparing micro-cutting and mini-cutting technique for the clonal propagation of Metrosideros excelsa
No full textpublic gardens for its foliage and attractive red flowers. M. excelsa plants are commercially propagated by soft and semi-ripe cuttings. Therefore, new and more reliable propagation techniques derived both from conventional and advanced propagation methods should be considered to support Metrosideros nursery development. The mini-cutting and micro-cutting techniques were compared for the clonal propagation of M. excelsa. Ex vitro rooted micro-cuttings resulted superior to mini-cuttings in terms of rooting percentage, root
number per cutting and root length by 23.5%, 42.5% and 2.4%, respectively. However, the mini-cutting technique can be considered an alternative reliable propagation method because it is less expensive than the micro-cutting technique and because it does not depend on tissue culture to supply stock plants
Neglected and Underutilized Plant Species in Horticultural and Ornamental Systems: Perspectives for Biodiversity, Nutraceuticals and Agricultural Sustainability
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Strawberry fields forever: That is, how many grams of plastics are used to grow a strawberry?
No full textIn important areas of the agricultural sector, plastic is one of the most important tools for improving the managerial and economic performance of companies. Horticultural production under protected cultivation, in particular, makes abundant use of plastic polymers-polymers that mostly turn into waste. This study aims to identify similar organisational models among farmers operating in the strawberry production sector in relation to their intention to recycle plastic material and which factors characterize these models (attitudes, subjective norms, perceived behavioural control, and socio-demographic characteristics) and to quantify the plastic used in relation to the different types of materials used. In order to achieve this aim, data coming from one of Italy's most specialized areas in the strawberry sector, Marsala, were analysed using a principal component analysis to identify latent factor and subsequently clustered in order to identify similar organisational models. The main findings show that behind a typical 250-gram basket of strawberries, the production process has generated more than 20 g of plastic waste, consisting of different polymers. In addition, younger farmers, who manage companies of smaller physical dimensions, and with a higher level of education, show a greater intention to join plastic recycling programs, guided by their attitudes, by the necessity to respond to social pressures, and by the ability to manage recycling programs. Our main result adds to previous knowledge that the informed producer (via greater awareness) is the key to solving the problem through improving environmental sustainability and creating a circular economy
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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